Apparatus and method for directing energy from a multi-element source

ABSTRACT

An apparatus for controlling the angular direction of energy emitted from a plurality of energy delivery devices. The apparatus includes a plurality of rods, each rod mechanically coupled to one of the energy delivery devices, to a stationary plate, and to a moveable plate. The stationary plate includes holes that are configured to receive a portion of a first rotatable joint that is mechanically coupled to each rod. The moveable plate includes holes that are configured to receive a portion of a second rotatable joint, the second rotatable joint slidingly engaging a portion of the respective rod. The angle of each rod changes when the moveable plate is moved in any direction with respect to the stationary plate. Changing the rod angle changes the angular direction of the energy emitted from the energy delivery devices such that the energy passes through an intended focal position.

CROSS-REFERENCE TO RELATED APPLICATIONS

The present application is a division of U.S. application Ser. No.15/981,383, titled “Apparatus and Method for Directing Energy from aMulti-Element Source,” filed on May 16, 2018, which is herebyincorporated by reference.

TECHNICAL FIELD

This application is generally related to apparatus, systems, and methodsfor controlling the direction of energy emitted by energy deliverydevices.

BACKGROUND

Ultrasound and other energy-delivery systems emit energy that is focusedinto or directed to a target region. These systems control the locationthat the energy is focused or directed by (a) physically adjusting theposition of the energy-delivery elements so that the energy is focusedor directed to the desired location, (b) adjusting the relative phaseand amplitude of the energy emitted by each energy-delivery element tobeam steer the energy to the desired location, or (c) a combination of(a) and (b). Since the relative phase and amplitude can be adjustedwithout physically moving the energy-delivery elements, beam steeringcan be performed more rapidly than physically moving the energy-deliverysystem. However, the ability to adjust the focus or direction of theenergy is limited in beam steering. Therefore, the energy-deliverysystem needs to be physically moved when the target region lies outsideof the limited adjustment range available in beam steering.

It would be desirable to increase the range over which the directionand/or focus of the energy-delivery elements can be adjusted withoutphysically moving the energy-delivery system.

FIG. 1 is a simplified diagram of an energy delivery system 10 accordingto the prior art. The energy delivery system 10 includes a plurality ofenergy-delivery devices 100 that emit energy into a respective region110. As illustrated, only a portion of the emitted energy passes throughthe desired target point 120. Therefore, it takes longer to provide agiven dose of energy to the target point 120 than it would if theenergy-delivery devices 100 were geometrically focused on the targetpoint 120. However, geometrically focusing the energy on the targetpoint 120 would decrease the angular area over which the energy-deliverydevices 100 that emit can emit energy.

It would be desirable to arrange the energy-delivery devices so thatthey can geometrically focus the energy at the desired target pointwhile maintaining the ability to emit the energy over a wide area.

SUMMARY

Example embodiments described herein have innovative features, no singleone of which is indispensable or solely responsible for their desirableattributes. The following description and drawings set forth certainillustrative implementations of the disclosure in detail, which areindicative of several exemplary ways in which the various principles ofthe disclosure may be carried out. The illustrative examples, however,are not exhaustive of the many possible embodiments of the disclosure.Without limiting the scope of the claims, some of the advantageousfeatures will now be summarized. Other objects, advantages and novelfeatures of the disclosure will be set forth in the following detaileddescription of the disclosure when considered in conjunction with thedrawings, which are intended to illustrate, not limit, the invention.

An aspect of the invention is directed to an apparatus comprising aplurality of energy delivery devices; a plurality of rods, each rodcomprising first and second ends, the first end mechanically coupled toone of said energy delivery devices; a plurality of first rotatablejoints, each first rotatable joint mechanically coupled to acorresponding rod; a plurality of second rotatable joints, each secondrotatable joint is slidingly engage a portion of the corresponding rod;a stationary plate comprising a plurality of stationary plate holes,each stationary plate hole configured to receive at least a portion ofone of said first rotatable joints to form a plurality of firstrotatable joint connections, each first rotatable joint rotatable withrespect to the stationary plate; and a moveable plate comprising aplurality of moveable plate holes, each moveable plate hole configuredto receive at least a portion of one of said second rotatable joints toform a plurality of second rotatable joint connections, each secondrotatable joint rotatable with respect to the moveable plate.

In one or more embodiments, for each rod the first rotatable joint isdisposed between the first end and the second rotatable joint. In one ormore embodiments, for each rod the first rotatable joint is disposedbetween the second end and the second rotatable joint. In one or moreembodiments, the stationary plate, the moveable plate, or both thestationary plate and the moveable plate is/are planar. In one or moreembodiments, the stationary plate, the moveable plate, or both thestationary plate and the moveable plate is/are curved. In one or moreembodiments, for each rod the first rotatable joint is integrallyconnected to the rod.

In one or more embodiments, the apparatus further comprises apositioning mechanism in mechanical communication with the moveableplate to change a position of the moveable plate with respect to thestationary plate. In one or more embodiments, the positioning mechanismis configured to change the position of the moveable plate along an axisto increase or decrease a distance between the moveable plate and thestationary plate. In one or more embodiments, each rod extends from thestationary plate to the moveable plate along a respective rod axis andthe positioning mechanism is configured to change the position of themoveable plate within a plane that is orthogonal to at least one of therod axes. In one or more embodiments, the positioning mechanismcomprises an x-y-z positioner.

In one or more embodiments, each rod extends from the stationary plateto the moveable plate along a respective rod axis and each rod isoriented at an angle, the angle between the rod axis and a referenceaxis; and a change in the position of the moveable plate with respect tothe stationary plate causes the angle to change. In one or moreembodiments, each energy delivery device emits energy in a directioncorresponding to the angle of the respective rod, and the change in theangle of the respective rod causes a corresponding change in thedirection of the energy emitted by the energy delivery device. In one ormore embodiments, the energy emitted by the energy delivery devices isfocused in a focal zone, and the change in the direction of the energyemitted by each energy delivery device causes a location of the focalzone to change.

In one or more embodiments, each energy delivery device comprises one ormore ultrasound transducer elements. In one or more embodiments, eachfirst rotatable joint comprises a first ball and each second rotatablejoint comprises a second ball, each first ball forming a first ballconnection with the stationary plate, each second ball forming a secondball connection with the secondary plate. In one or more embodiments, ahole is defined in each second ball to slidingly engage the portion ofthe corresponding rod. In one or more embodiments, the first and secondrotatable joints have two rotational degrees of freedom and the secondrotatable joint has a translational degree of freedom with respect tothe corresponding rod. In one or more embodiments, each first rotatablejoint comprises a first gimbal and each second rotatable joint comprisesa second gimbal.

Another aspect of the invention is directed to a method of controlling adirection of energy emitted by energy delivery devices, the methodcomprising: emitting energy from each energy delivery device in anangular direction, each energy delivery device mechanically coupled to afirst end of a rod that extends from a moveable plate to a stationaryplate along a rod axis, the rod mechanically coupled to a firstrotatable joint disposed at least in part in a corresponding hole in thestationary plate, wherein the angular direction is defined by an anglebetween the rod axis and a reference axis; with a positioning mechanismin mechanical communication with the moveable plate, changing a positionof the moveable plate with respect to the stationary plate, the moveableplate in mechanical communication with each rod via a correspondingsecond rotatable joint, each second rotatable joint disposed at least inpart in a corresponding hole in the moveable plate, wherein a portion ofthe rod is slidingly engaged with the second rotatable joint; rotatingthe first and second rotatable joints with respect to the stationary andmoveable plates, respectively, so that each rod continues to extend fromthe moveable plate to the stationary plate along the rod axis when theposition of the moveable plate is changed; and changing the angulardirection of the energy emitted from each energy delivery device.

In one or more embodiments, the method further comprises arranging therods so that at least a portion of the energy from each energy deliverydevice passes through a focal zone. In one or more embodiments, changingthe angular direction of the energy emitted from each energy deliverydevice changes a location of the focal zone. In one or more embodiments,changing the position of the moveable plate comprises moving themoveable plate parallel to a plane that is orthogonal to at least one ofthe rod axes. In one or more embodiments, changing the position of themoveable plate comprises moving the moveable plate closer to or awayfrom the stationary plate.

In one or more embodiments, each energy delivery device comprises one ormore ultrasound transducer elements, and the energy emitted from eachenergy delivery device comprises ultrasound mechanical energy. In one ormore embodiments, the method further comprises adjusting the angulardirection of the energy according to a treatment plan. In one or moreembodiments, the method further comprises receiving, at a computer,magnetic resonance data of a target region in a subject, the magneticresonance data indicating a measured angular direction of the ultrasoundtransducer elements; comparing the measured angular direction of theultrasound transducer elements with a target angular direction in thetreatment plan; and adjusting the position of the moveable plate whenthe measured angular direction of the ultrasound transducer elements isdifferent than the target angular direction in the treatment plan.

In one or more embodiments, the method further comprises mechanicallycoupling a first ball to the first end of each rod, the first balldisposed at least in part in the corresponding hole in the stationaryplate. In one or more embodiments, the method further comprisesmechanically coupling a second ball to the portion of each rod, thesecond ball disposed at least in part in the corresponding hole in themoveable plate.

BRIEF DESCRIPTION OF THE DRAWINGS

For a fuller understanding of the nature and advantages of the presentconcepts, reference is made to the following detailed description ofpreferred embodiments and in connection with the accompanying drawings,in which:

FIG. 1 is a simplified diagram of an energy delivery system according tothe prior art;

FIG. 2 is a diagram of one type of system in which at least some of theapparatus and/or methods disclosed herein are employed, in accordancewith at least some embodiments;

FIG. 3 is a simplified view of an ultrasound apparatus in a first stateaccording to one or more embodiments;

FIG. 4 illustrates the ultrasound apparatus in a second state after thesecond support plate has been moved in a first direction according toone or more embodiments;

FIG. 5 illustrates the ultrasound apparatus in a second state after thefirst support plate has been moved in a second direction according toone or more embodiments;

FIG. 6 illustrates the ultrasound apparatus in a third state after thesecond support plate has been moved in a third direction according toone or more embodiments;

FIG. 7 illustrates the ultrasound apparatus in a fourth state after thesecond support plate has been moved in a fourth direction according toone or more embodiments;

FIG. 8 is a simplified view of an ultrasound apparatus in a first stateaccording to one or more embodiments;

FIG. 9 is a simplified view of an ultrasound apparatus in a second stateaccording to one or more embodiments;

FIG. 10A is a simplified view of an ultrasound apparatus in a firststate according to one or more embodiments;

FIG. 10B is a simplified view of an ultrasound apparatus according toone or more embodiments;

FIG. 11 is a simplified view of the ultrasound apparatus illustrated inFIG. 10A in a second state according to one or more embodiments;

FIG. 12 is a perspective view of a transducer assembly according to oneor more embodiments;

FIG. 13 is a perspective view of a transducer assembly according to oneor more embodiments;

FIG. 14 is a perspective view of a system according to one or moreembodiments;

FIG. 15 is a side view of the system illustrated in FIG. 14 thatprovides a more detailed view of the positioning apparatus;

FIG. 16 is a cross section of the system illustrated in FIG. 14 ;

FIG. 17 is a detailed view of a portion of the cross section of thesystem illustrated in FIG. 16 ; and

FIG. 18 is a flow chart of a method for controlling the direction ofenergy emitted by energy delivery devices.

DETAILED DESCRIPTION

This disclosure is broadly applicable to apparatus, systems, and methodsfor controlling the direction of energy emitted by many types of energydelivery devices. Examples of such energy delivery devices includeultrasound elements, lasers, mirrors (e.g., for solar or otherapplications), electromagnetic signals (e.g., radio-frequency (RF)signals, light), and others (e.g., with positive interference). Withoutlimiting the scope of the disclosure, several of the embodimentsprovided herein are described with respect to ultrasound energy deliverydevices (e.g., ultrasound elements). It is to be understood, however,that those embodiments are also applicable to other types of energydelivery elements. Thus, ultrasound delivery devices are an exemplaryembodiment of energy delivery devices, and references to ultrasounddelivery devices (or to ultrasound elements) are provided as anon-limiting example of energy delivery devices.

Energy devices are mechanically coupled to respective rods that extendfrom a first plate to a second plate. Each rod is mechanically coupledto the first and second plates via first and second rotatable jointconnections, respectively. A first rotatable joint is mechanicallycoupled (e.g., attached, integrally connected, etc.) to each rod. Thefirst rotatable joint is at least partially disposed in a correspondinghole in the first plate to form the first rotatable joint connection. Asecond rotatable joint slidingly receives or engages a portion of therespective rod. The second rotatable joint is at least partiallydisposed in a corresponding hole in the second plate to form the secondrotatable joint connection. In some examples, the first and/or secondrotatable joints are balls, gimbals, pivot joints, swivel joints,bearings (e.g., slewing bearings), and/or other rotatable joints.

Each energy delivery device emits energy in a respective angulardirection, which can be the same or different between energy deliverydevices. The angular direction of each energy delivery device ismeasured according to the angle between the rod axis and a referenceaxis. Each rod extends from the first plate to the second plate alongthe rod axis.

One or both of the first and second plates is moveable with respect tothe other plate. For example, the first plate can be moveable withrespect to the second plate using a mechanical positioning mechanism.The first and second rotatable joint connections cause the rod to movewhen the first plate is moved with respect to the second plate. Sincethe second plate is stationary and the rod extends from the first plateto the second plate, the movement of the first plate causes the anglebetween the rod axis and a reference axis to change. The change in anglecauses a corresponding change in the angular direction that the energyis emitted from the energy delivery device.

FIG. 2 is a diagram of one type of system 200 in which at least some ofthe apparatus, systems, and/or methods disclosed herein are employed, inaccordance with at least some embodiments. The system 200, which is amedical system, includes a patient support 206 (on which a patient 208is shown), a magnetic resonance system 202 and an image guided energydelivery system 204.

The magnetic resonance system 202 includes a magnet 210 disposed aboutan opening 212, an imaging zone 214 in which the magnetic field isstrong and uniform enough to perform magnetic resonance imaging, a setof magnetic field gradient coils 216 to change the magnetic fieldrapidly to enable the spatial coding of MRI signals, a magnetic fieldgradient coil power supply 218 that supplies current to the magneticfield gradient coils 216 and is controlled as a function of time, atransmit/receive coil 220 (also known as a “body” coil) to manipulatethe orientations of magnetic spins within the imaging zone 214, a radiofrequency transceiver 222 connected to the transmit/receive coil 220,and a computer 224, which performs tasks (by executing instructionsand/or otherwise) to facilitate operation of the MRI system 202 and iscoupled to the radio frequency transceiver 222, the magnetic fieldgradient coil power supply 218, and the image guided energy deliverysystem 204.

The image guided energy delivery system 204 performs image guidedtherapy (e.g., thermal therapy) and can implement one or more aspectsand/or embodiments disclosed herein (or portion(s) thereof) to deliverenergy (e.g., ultrasound energy) in multiple angular directions to treata treatment region.

The MRI computer 224 can include more than one computer in someembodiments, which can be dedicated for the MRI system 202. In at leastsome embodiments, the MRI computer 224 and/or one or more othercomputing devices (not shown) in and/or coupled to the system 200 mayalso perform one or more tasks (by executing instructions and/orotherwise) to implement one or more aspects and/or embodiments disclosedherein (or portion(s) thereof) to control the angular direction of theenergy emitted by energy delivery devices in the image guided energydelivery system 204. For example, the computer 224 and/or one or moreother computing devices (not shown) in and/or coupled to the system 200can adjust the angle of a rod that is mechanically coupled to eachenergy delivery device (e.g., by adjusting the position of a first platein mechanical communication with the rod) as described herein. One ormore of the computers, including computer 224, can include a treatmentplan for the patient 208 that includes the target treatment region andthe desired or minimal energy (e.g., thermal) dose for the targettreatment region. The computer(s) can use images from the magneticresonance system 202 to image guide the angular direction of the energyemitted by the energy delivery devices. In some embodiments, one or morededicated computers control the image guided energy delivery system 204.Some or all of the foregoing computers can be in communication with oneanother (e.g., over a local area network, a wide area network, acellular network, a WiFi network, or other network), for example througha software-controlled link.

FIG. 3 is a simplified view of an ultrasound apparatus 30 in a firststate according to one or more embodiments. The apparatus 30 includes aplurality of transducer assemblies 300, a first support plate 320, and asecond support plate 330. Each transducer assembly 300 includes anultrasound transducer element 301, a rod 310, and a first ball 345. Thetransducer element 301 is disposed on a first end 312 of the rod 310.Each rod 310 is in mechanical communication with the first and secondsupport plates 320, 330 via first and second ball connections 340, 350.The first ball connection 340 is disposed proximal to the first end 312of the rod 310. The second ball connection 350 is disposed proximal to asecond end 314 of the rod 310. The first and second ball connections340, 350 can include ball joints in some embodiments.

The first ball 345 is mechanically coupled (e.g., attached, adhered,secured, etc.) to the rod 310 in a fixed position such that the firstball 345 does not move relative to the rod 310. In some embodiments, therod 310 and first ball 345 are integrally connected as a single unit. Inother embodiments, the rod 310 and first ball 345 are separate unitsthat are fixedly attached to one another. The second ball connection 350includes a second ball 355 that is moveable and/or slideable withrespect to the rod 310. For example, the second ball 355 can include ahole or aperture to receive and mechanically engage (e.g., slidinglyengage, slidingly receive, and/or slidingly couple to) a portion of therod 310. The rod 310 can slide towards or away from the second ball 355,along the axis 360 of each rod 310, to adjust the relative axialposition of the rod 310 with respect to the second ball 355.

The first support plate 320 includes a plurality of holes 325 to receivea first portion of each first ball 345 to form the first ballconnections 340. A second portion of each first ball 345 rests on thefirst support plate 320 around the holes 325 to mechanically supportfirst ball 345. Since the first balls 345 are attached to the rods 310,mechanically supporting the first balls 345 on the first support plate320 also mechanically supports the rods 310 and the ultrasoundtransducer elements 301 attached thereto. The position of the firstballs 345 with respect to the first support plate 320 is fixed. However,the first balls 345 can rotate to adjust the angle 375 of each rod 310,in the x-z plane and/or the y-z plane, with respect to a correspondingreference axis 370. Only one reference axis 370 is illustrated in FIG. 3for clarity. Thus, the rods 310 have a single degree of freedom(rotation) in the first ball connections 340.

The second support plate 330 includes a plurality of holes 335 toreceive a first portion of each second ball 355 to form the second ballconnections 350. A second portion of each second ball 355 rests on thesecond support plate 330 around the holes 335 to mechanically supportthe second balls 355. The position of the second balls 355 with respectto the second support plate 330 is fixed. However, the second balls 355can rotate with the first balls 345 to adjust the angle 375 of each rod310 with respect to the corresponding reference axis 370. In addition,the axial position of each rod 310 with respect to the correspondingsecond ball 355 is adjustable, as discussed above. Thus, the rods 310have two degrees of freedom (rotation and axial position) in the secondball connections 350.

Rotating the first and second balls 345, 355 causes the angle 375 tochange, which changes the angular direction of the acoustic energy 302emitted from each transducer element(s) 301. In some embodiments, atleast one of the first and second ball connections 340, 350 prevents therods 310 from rotating about the rod axis 360, for example to preventthe twisting of any wires that may be connected to the ultrasoundtransducer elements 301.

It is noted that FIGS. 3-11 illustrate that each first ball 345 isdisposed between the first end 312 of the rod 310 and the second ball355. However, in other embodiments, each first ball 345 can be disposedbetween the second end 314 of the rod 310 and the second ball 355.

In FIG. 3 , the first and second support plates 320, 330 are illustratedas inwardly curved, for example in a high-intensity focused ultrasound(HIFU) system. In addition, or in the alternative, one or both supportplates 320, 330 can be curved outwardly. In addition, or in thealternative, one or both support plates 320, 330 can be planar.

The relative position of the support plates 320, 330 with respect to oneanother is adjustable. For example, the second support plate 330 can bemoved axially or radially with respect to the first support plate 320.In another example, the second support plate 330 can be moved closer toor further away from the first plate 320. In yet another example, thesecond support plate 330 can be moved both (a) axially (e.g., parallelto the “x” axis”) or radially with respect to the first support plate320 and (b) closer to or further away from the first plate 320 (e.g.,parallel to the “z” axis). Though the adjustment of the relativepositions of the support plates 320, 330 has been described with respectto moving the second support plate 330 (i.e., the first support plate320 can be stationary and the second support plate 330 can be moveable),it is noted that the same relative position adjustment can be made bymoving the first support plate 320 (i.e., the first support plate 320can be moveable and the second support plate 330 can be stationary). Forexample, moving the second support plate 330 axially to the left in FIG.3 is equivalent to moving the first support plate 320 axially to theright in FIG. 3 . Likewise, moving the second support plate 330 upwardsin FIG. 3 (closer to the first support plate 320) is equivalent tomoving the first support plate 320 downwards (closer to second supportplate 330) in FIG. 3 . Combinations of the foregoing are also possible.Finally, both support plates 320, 330 can be moved (i.e., the firstsupport plate 320 and the second support plate 330 can be moveable) inopposite directions (e.g., one to the left, the other to the right) toachieve the equivalent relative position adjustments discussed above.

The first and/or second support plates 320, 330 can be moved with apositioning mechanism, such as an x-y positioner or an x-y-z positioner.The positioning mechanism can include one or more geared connections,rotatable by a motor or by hydraulics, to move one of the support plates320, 330 in a first, second, and/or third directions (e.g., in the “x,”“y,” and/or “z” directions). In addition, or in the alternative, thepositioning mechanism can include an actuator or other device that canbe electromechanically or pneumatically operated. The positioningmechanism can be controlled by a computer that also controls theultrasound transducer elements 301, a separate computer, or computer224. The computer that controls the positioning mechanism can receivefeedback from images provided by the magnetic resonance system 202 toimage guide the positioning mechanism and/or to electronically focus theultrasound transducer elements 301.

The ultrasound transducer elements 301 generate acoustic energy 302 thatis geometrically focused and/or electronically focused through beamformsteering (e.g., by adjusting the relative phase of the acoustic energy302 generated by each transducer element 301) towards a focal zone 304.An example of a geometrically-focused ultrasound system ishigh-intensity focused ultrasound (HIFU). In some embodiments, theultrasound apparatus 30 is part of a HIFU system. The location of thefocal zone 304 can be adjusted geometrically by moving the first and/orsecond support plates 310, 320.

FIG. 4 illustrates the ultrasound apparatus 30 in a second state afterthe second support plate 320 has been moved in a first direction. InFIG. 4 , the second support plate 320 has been moved 400 to the left(e.g., parallel to the “x” axis), which causes the second balls 355 andthe second end 314 of the rods 310 to move to the left. As a result, theangle 375 of each rod 310 changes (e.g., decreased with respect toreference axis 370) to geometrically move 410 the focal zone 304 of thetransducer elements 301 to the right (e.g., parallel to the “x” axis).In other words, moving the second support plate 320 in a first directioncauses the location or position of focal zone 304 to move in a seconddirection, where the second direction is the opposite of the firstdirection. It is noted that the location of the focal zone 304 can beadjusted further (or fine-tuned) by beamform steering. The first andsecond balls 345, 355 rotate according to the change in the angle 375.

As discussed above, the same result can be accomplished by moving thefirst support plate 310 to the right. Moving the first support plate 310to the right causes the first balls 345 and the first end 312 of therods to move to the right, which results in the same angle 375adjustment of each rod 310 as discussed above. Thus, moving the firstsupport plate 310 in a first direction causes the focal zone 304 to movein a first direction.

Adjusting the relative position of the support plates 310, 320 (e.g.,moving the second support plate 320 to the left) can cause a change inthe distance 380 between the support plates 310, 320. For example,moving the second support plate 320 to the left increases the distance380 between the support plates 310, 320. The rod 310 can slide through ahole or aperture in the second ball 355 to change the length of rod 310between the first and second balls 345, 355 according to the change indistance 380.

It is noted that the second support plate 320 (and/or the first supportplate 310) can be moved 500 in the “y” direction to geometrically move510 the focal zone 304 of the transducer elements 301 with respect tothe “y” direction, as illustrated in FIG. 5 . Moving 500 the secondsupport plate 320 (and/or the first support plate 310) in the “y”direction results in an equivalent change in state of the system 30 asdescribed above with respect to FIG. 4 , which illustrates a change instate of system 30 with respect to the “x” direction. For example,moving 500 the second support plate 320 in the “y” direction causes thefirst and second balls 345, 355 to rotate to adjust the angle 575 ofeach rod 310, in the y-z plane, with respect to a correspondingreference axis 570.

It is also noted that the second support plate 320 (and/or the firstsupport plate 310) can be moved (e.g., moved 400, 500) in the “x” and“y” directions (i.e., within the x-y plane) to move (e.g., move 410,510) the focal zone 304 of the transducer elements 301 with respect tothe “x” and “y” directions.

FIG. 6 illustrates the ultrasound apparatus 30 in a third state afterthe second support plate 320 has been moved in a third direction. InFIG. 6 , the second support plate 320 has been moved 600 closer to thefirst support plate 310 (e.g., parallel to the “z” axis), which causesthe focal zone 304 to geometrically move 610 closer to the first supportplate 310 such that the ultrasound transducers 301 have a reduced focallength compared to when the ultrasound apparatus 30 is in the firststate, as illustrated in FIG. 3 .

In the third state, the second end 314 of the outer rods 310 (alsolabeled as 611, 612) move away from each other, and away from the middlerod 310 (also labeled as 613). Conversely, the first end 312 of theouter rods 310 move inwardly, which causes the focal zone 304 togeometrically move 610 closer to the first support plate 310. Forexample, in the third state, the angle 375 of the right-hand rod 310(also labeled as rod 611) increases. In addition, the angle 675 of theleft-hand rod 310 (also labeled as rod 612), with respect to referenceaxis 610, increases. However, the axis 360 (and corresponding angle) ofthe middle rod 310 (also labeled as rod 613) continues to be in parallelwith reference axis 370.

FIG. 7 illustrates the ultrasound apparatus 30 in a fourth state afterthe second support plate 320 has been moved in a fourth direction. InFIG. 6 , the second support plate 320 has been moved 700 away from thefirst support plate 310 (e.g., parallel to the “z” axis), which causesthe focal zone 304 to geometrically move 710 away from the first supportplate 310 such that the ultrasound transducers 301 have an increasedfocal length compared to when the ultrasound apparatus 30 is in thefirst state, as illustrated in FIG. 3 .

In the fourth state, the second end 314 of the outer rods 310 (alsolabeled as 611, 612) move closer from each other, and away from themiddle rod 310 (also labeled as 613). Conversely, the first end 312 ofthe outer rods 310 move inwardly, which causes the focal zone 304 togeometrically move 710 away from the first support plate 310. Forexample, in the third state, the angle 375 of the right-hand rod 310(also labeled as rod 611) decreases. In addition, the angle 675 of theleft-hand rod 310 (also labeled as rod 612), with respect to referenceaxis 610, decreases. However, the axis 360 (and corresponding angle) ofthe middle rod 310 (also labeled as rod 613) continues to be in parallelwith reference axis 370.

Though FIGS. 4-7 illustrate the second plate 330 moving, with respect tothe first plate 320, in only in the “x” direction, the “y” direction, orthe “z” direction, it is noted that combinations of any of the foregoingare possible. For example, the second plate 330 can move in both the “x”and “y” directions (i.e., in the x-y plane), in both the “x” and “z”directions (i.e., in the x-z plane), in both the “y” and “z” directions(i.e., in the y-z plane), or in the “x,” “y,” and “z” directions. Asdescribed above, the first plate 320 can also move with respect to thesecond plate 330, and thus can move in any or all of the “x,” “y,” and“z” directions. In some embodiments, both plates 320, 330 can move inany or all of the “x,” “y,” and “z” directions with respect to oneanother.

FIG. 8 is a simplified view of an ultrasound apparatus 80 in a firststate according to one or more embodiments. The apparatus 80 is the sameas apparatus 30 except that the first and second support plates 320, 330are planar.

In some embodiments, a first face 321 of the first support plate 320(e.g., facing away from the second support plate 330) is planar and asecond face 322 of the first support plate 320 (e.g., facing the secondsupport plate 330) is not planar (e.g., is curved). In some embodiments,the first face 321 of the first support plate 320 is not planar (e.g.,is curved). and the second face 322 of the first support plate 320 isplanar. In some embodiments, a first face 331 of the second supportplate 330 (e.g., facing away from the first support plate 320) is planarand a second face 332 of the second support plate 330 (e.g., facing thefirst support plate 320) is not planar (e.g., is curved). In someembodiments, the first face 331 of the second support plate 330 is notplanar (e.g., is curved). and the second face 332 of the second supportplate 330 is planar.

FIG. 9 is a simplified view of the ultrasound apparatus 80 in a secondstate according to one or more embodiments. In FIG. 9 , the secondsupport plate 330 is moved 900 to the left (e.g., a first directionparallel to the “x” axis), which causes the focal zone 304 to move 910to the right (e.g., a second direction parallel to the “x” axis, thesecond direction being the opposite of the first direction). The angle375 changes as a result of the movement 900 of the second support plate330. The vertex of angle 375 is not illustrated in FIG. 9 since it wouldbe located off the page. Movement 900 is similar to the relativemovement of the second support plate 330 in apparatus 30 in theembodiment described above with respect to FIG. 4 .

The first and/or second support plates 320, 330 in apparatus 80 can bemoved in any direction with respect to one another, similar to the firstand/or second support plates 320, 330 in apparatus 30 described above.For simplicity and brevity, the various permutations of moving the firstand/or second support plates 320, 330 in apparatus 80 in each directionin the x-y-z coordinate system are not illustrated though they would besimilar to the relative movement of the first and second support plates320, 330 in apparatus 30 (e.g., in FIGS. 4-7 ).

FIG. 10A is a simplified view of an ultrasound apparatus 1000A in afirst state according to one or more embodiments. The apparatus 80 isthe same as apparatus 30 and 80 except that the first support plate 320is planar and the second support plate 330 is curved inwardly. Thus,ultrasound apparatus 1000A is a hybrid of apparatus 30 and 80. In otherembodiments, the first support plate 320 can be curved and the secondsupport plate 330 can be planar. The first and/or second support plates320, 330 can be curved inwardly or outwardly in some embodiments.

FIG. 10B is a simplified view of an ultrasound apparatus 1000B accordingto one or more embodiments. The apparatus 1000B is the same as apparatus30, 80, and 1000A except that the first support plate 320 is curvedoutwardly and the second support plate 330 is planar.

FIG. 11 is a simplified view of the ultrasound apparatus 1000Aillustrated in FIG. 10A in a second state according to one or moreembodiments. In FIG. 11 , the second support plate 330 is moved 1001 tothe left (e.g., a first direction parallel to the “x” axis), whichcauses the focal zone 304 to move 1010 to the right (e.g., a seconddirection parallel to the “x” axis, the second direction being theopposite of the first direction). The angle 375 changes as a result ofthe movement 1001 of the second support plate 330. The vertex of angle375 is not illustrated in FIG. 11 since it would be located off thepage. Movement 1001 is similar to the relative movement of the secondsupport plate 330 in apparatus 30, 80 in the embodiment described abovewith respect to FIGS. 4 and 9 , respectively.

The first and/or second support plates 320, 330 in apparatus 1000A canbe moved in any direction with respect to one another, similar to thefirst and/or second support plates 320, 330 in apparatus 30, 80described above. For simplicity and brevity, the various permutations ofmoving the first and/or second support plates 320, 330 in apparatus1000A in each direction in the x-y-z coordinate system are notillustrated though they would be similar to the relative movement of thefirst and second support plates 320, 330 in apparatus 30, 80 (e.g., inFIGS. 4-9 ).

FIG. 12 is a perspective view of a transducer assembly 1200 according toone or more embodiments. The assembly 1200 includes at least onetransducer element 1201, a rod 1210, and a ball 1245. The transducerelement(s) 1201 are mechanically coupled (e.g., attached, adhered,secured, etc.) to a first end 1212 of the rod 1210. The ball 1245 isdisposed on the rod 1210 proximal to its first end 1212. In someembodiments, the rod 1210 includes the ball 1245, in which case the rod1210 and the ball 1245 are integrally connected as a single unit. Inother embodiments, the ball 1245 is mechanically coupled (e.g.,attached, adhered, secured, etc.) to the rod 1210. The transducerelement(s) 1201 can be powered and controlled by electrical signalsreceived from one or more wires 1220 that pass through an electricalconduit 1230 defined in the rod 1210 and ball 1245 and through thesecond end 1214 of the rod 1210. Alternatively, the transducerelement(s) 1201 can be powered and controlled by electrical signalsreceived from one or more wires that extend from a lower surface 1250 ofthe transducer element(s) 1201 across an upper surface of the firstplate (e.g., first plate 320).

The transducer assembly 1200 can be the same as or similar to transducerassemblies 300 discussed above. For example, rod 1210, transducerelement(s) 1201, and/or ball 1245 can be the same as or similar to rod310, transducer element(s) 300, and/or first ball 345. Thus, theultrasound apparatus 30, 80 can include or more transducer assemblies1200.

FIG. 13 is a perspective view of a transducer assembly 1300 according toone or more embodiments. The assembly 1300 the same as assembly 1200except that the transducer element(s) 1201 is/are disposed on the secondend 1214 of the rod 1210 and the wire(s) 1220 pass through theelectrical conduit 1230 via the first end 1212 of the rod 1210. Sincethe transducer element(s) 1201 is/are disposed on the second end 1214 ofthe rod 1210, the ball 1245 is disposed further away from the transducerelement(s) 1201 in assembly 1300 than in assembly 1200.

The transducer assembly 1300 can be the same as or similar to transducerassemblies 300 discussed above. For example, rod 1210, transducerelement(s) 1201, and/or ball 1245 can be the same as or similar to rod310, transducer element(s) 300, and/or second ball 355. Thus, theultrasound apparatus 30, 80 can include or more transducer assemblies1300.

FIG. 14 is a perspective view of a system 1400 according to one or moreembodiments. The system 1400 includes a first plate 1420, a second plate1430, a plurality of transducer assemblies 1401, and a positioningapparatus 1450. The first and second plates 1420, 1430 can be the sameas or similar to the first and second plates 320, 330. A stand orsupport 1410 is mechanically coupled to or integrally connected to thefirst plate 1420 to maintain the position of the first plate 1420. Thepositioning apparatus 1450 is in mechanical communication with thesecond plate 1430 to move (e.g., change the position of) the secondplate 1430 relative to the first plate 1420. Thus, the first plate 1420is stationary and the second plate 1430 is moveable. In otherembodiments, the second plate 1430 can be stationary and the first plate1420 can be moveable, or both the first and second plates 1420, 1403 canbe moveable.

Each transducer assembly 1401 can be the same as or similar totransducer assembly 300, transducer assembly 1200, and/or transducerassembly 1300. For example, one or more transducer assemblies 1401 canbe the same as or similar to the transducer assembly 1200 and one ormore transducer assemblies 1401 can be the same as or similar totransducer assembly 1300. In another example, one or more transducerassemblies 1401 can be the same as or similar to transducer assembly 300and one or more transducer assemblies 1401 can be the same as or similarto transducer assembly 1300. In another example, one or more transducerassemblies 1401 can be the same as or similar to transducer assembly 300and one or more transducer assemblies 1401 can be the same as or similarto transducer assembly 1200. In yet another example, one or moretransducer assemblies 1401 can be the same as or similar to transducerassembly 300, one or more transducer assemblies 1401 can be the same asor similar to transducer assembly 1200, and/or one or more transducerassemblies 1401 can be the same as or similar to transducer assembly1300.

The positioning apparatus 1450 includes a first mechanism 1460 to movethe second plate 1430 in the “y” direction (e.g., along a first axis), asecond mechanism 1470 to move the second plate 1430 in the “x” direction(e.g., along a second axis that is orthogonal to the first axis), athird mechanism 1482 to move the second plate 1430 in the “x” direction(e.g., along a third axis that is orthogonal to the first and secondaxes), and a platform 1480. As such, the positioning apparatus 1450 canmove the second plate 1430 in any direction in three-dimensional space(e.g., in the “x,” “y,” and/or “z” directions). In some embodiments, thepositioning apparatus 1450 is an x-y-z positioner.

The first mechanism 1460 includes gears 1461 (on the left and right sideof shaft 1462) and a toothed rail or rod 1463 that engage one another(e.g., as a rack and pinion connection). The gears 1461 can be driven(e.g., rotated) manually or by a motor, which can be in communicationwith computer 1490. The rotation of the gears 1461 is translated to thetoothed rail or rod 1463, which is mechanically attached to platform1480 and extends in parallel with the “y” axis, to cause the secondplate 1430 to move linearly and in parallel with the “y” axis. Thesecond plate 1430 can move in any direction with respect to platform1480.

The second mechanism 1470 includes a screw 1472 that moves block 1474(illustrated in FIG. 15 ) parallel to the “x” axis. In turn, block 1474moves horizontal rod 1476 (illustrated in FIG. 15 ) parallel to the “x”axis, which causes the platform 1480 to move parallel to the “x” axis.Thus, rotating the screw 1472 causes the platform 1480 and second plate1430 to move parallel to the “x” axis. It is noted that the horizontalrod 1476 extends through a hole defined in the block 1474 to allow themto slidingly engage each other parallel to the “y” axis. Screw 1472 canbe rotated manually or by a motor, which can be in communication withcomputer 1490.

The third mechanism 1482 includes a gear 1481 and a toothed rail or rod1483 that engage one another (e.g., as a rack and pinion connection).The toothed rail or rod 1483 can move or slide with respect to platform1480. Rotating gear 1481 (e.g., manually or by a motor) causes thetoothed rail or rod 1483 to slide relative to platform 1480 to turnpinions 1484 that engage a vertical toothed rail or rod (extendingparallel to the “z” axis; not illustrated) that is attached to secondplate 1430, thereby moving the second plate 1430 parallel to the “z”axis to increase or decrease the distance between first and secondplates 1420, 1430. Gear 1481 can be rotated manually or by a motor,which can be in communication with computer 1490.

In other embodiments, the first, second, and/or third mechanisms 1460,1470, 1480 can include the same mechanisms (e.g., they can each includea gear and a toothed bar (e.g., gear 1461 and toothed bar 1463), ascrew, a linear actuator, or other mechanism) that can translate theplatform second plate 1430 parallel to the “y,” “x,” and “z” axes,respectively.

The positioning mechanism 1460 can be controlled by a computer 1490. Thecomputer 1490 can be the same as the computer or controller that alsocontrols the ultrasound transducer elements 301, the same as thecomputer 224 associated with MRI system 202, or it can be a separatecomputer. The computer 1490 can receive feedback from images provided bythe magnetic resonance system 202 to image guide the positioningmechanism 1460 and/or to electronically focus the ultrasound transducerelements.

FIG. 15 is a side view of the system 1400 illustrated in FIG. 14 thatprovides a more detailed view of the positioning apparatus 1450.

FIG. 16 is a cross section of the system 1400 illustrated in FIG. 14through plane A-A. The cross section reveals the first and second ballconnections 1640, 1650, which can be the same as or similar to first andsecond ball connections 340, 350, respectively. The cross section alsoillustrates the rods 1610 of the transducer assemblies 1401. Rods 1610can be the same as or similar to rods 310.

FIG. 17 is a detailed view 1700 of a portion of the cross section of thesystem 1400 illustrated in FIG. 16 . The detailed view 1700 furtherillustrates the transducer assemblies 1401 and the first and second ballconnections 1640, 1650. As illustrated, each transducer assembly 1401includes a rod 1610, a ball 1645, and one or more transducer elements1601. A portion of the ball 1645 rests in a hole 1625 in the firstsupport plate 1420 to mechanically support the transducer assembly 1401in the first ball connection 1640. As discussed above, the ball 1645 andthe rod 1610 can be a single unit integrally connected together orseparate units that are attached or affixed to one another. A portion ofa second ball 1655 rests in a hole 1635 in the second support plate1430. The rod 1610 extends through a hole 1657 in the second ball 1655to form the second ball connection 1650. A recessed region 1710 isdisposed proximal to each ball 1645, 1655 to secure the ball 1645, 1655in the respective hole 1625, 1635.

As discussed above with respect to apparatus 30, 80, the balls 1645,1655 can rotate with respect to the support plates 1420, 1430,respectively, similar to the embodiments discussed above. In addition,the rod 1610 can slide or move axially with respect to the hole 1657 inthe second ball 1655.

FIG. 18 is a flow chart 1800 of a method for controlling the directionof energy emitted by energy delivery devices. The method in flow chart1800 can be performed with one or more of the apparatus and/or systemsdescribed herein. In step 1810, energy is emitted from each energydelivery device in an angular direction. Each energy delivery device ismechanically coupled to a first end of a rod that extends from amoveable plate to a stationary plate along a rod axis. In each energydelivery device, the rod is mechanically coupled to a first balldisposed at least in part in a corresponding hole in the stationaryplate. The angular direction is defined by an angle (e.g., angle 375)between the rod axis and a reference axis.

In some embodiments, each energy delivery device includes or consists ofone or more ultrasound transducer elements, and the energy emitted fromeach energy delivery device comprises ultrasound mechanical energy.

In step 1820, the position of the moveable plate with respect to thestationary plate is changed using a positioning mechanism in mechanicalcommunication with the moveable plate. The moveable plate is inmechanical communication with each rod via a corresponding second ball.Each second ball is disposed at least in part in a corresponding hole inthe moveable plate. In each energy delivery device, a portion of the rodis disposed in a hole defined in the second ball.

In some embodiments, the moveable plate can be moved parallel to and/ororthogonal to a plane that is orthogonal to at least one of the rodaxes. In some embodiments, the moveable plate can be moved closer to oraway from the stationary plate.

In step 1830, the first and second balls are rotated with respect to thestationary and moveable plates, respectively, so that each rod continuesto extend from the moveable plate to the stationary plate along the rodaxis when the position of the moveable plate is changed in step 1820.

In step 1840, the angular direction of the energy emitted from eachenergy delivery device is changed.

In some embodiments, the rods can be arranged so that at least a portionof the energy from each energy delivery device passes through a focalzone (e.g., focal zone 304). In some embodiments, changing the angulardirection of the energy emitted from each energy delivery device changesa location of the focal zone. The angular direction of the energyemitted from each energy delivery and the location of the focal zone canbe adjusted according to a treatment plan, for example to apply aminimum dose of energy to a treatment region (e.g., in a subject). In aspecific embodiment, the treatment plan can be to heat a treatmentregion of a subject to a minimum temperature to cause necrosis of thetissue to treat a tumor or disease.

In some embodiments, the method can include adjusting or fine-tuning theangular direction of the energy delivery devices based on feedbackinformation. For example, the method can include receiving, at acomputer, magnetic resonance data of a target region in a subject, themagnetic resonance data indicating a measured angular direction of theenergy delivery devices (e.g., ultrasound transducer elements). Themethod can also include comparing the measured angular direction of theultrasound transducer elements with a target angular direction in atreatment plan. The method can also include adjusting the position ofthe moveable plate when the measured angular direction of the ultrasoundtransducer elements is different than the target angular direction inthe treatment plan.

The foregoing describes embodiments that include first and second balls(e.g., first and second balls 345, 355) that form respective first andsecond ball connections (e.g., first and second ball connections 340,350) with respective first and second support plates (e.g., first andsecond support plates 320, 330). In other embodiments, the first and/orsecond ball(s) can be another type of rotatable joint, such as a gimbal,a pivot joint, a swivel joint, a bearing (e.g., a slewing bearing), orother rotatable joint. The first and second rotatable joints form firstand second rotatable joint connections (corresponding to the first andsecond ball connections described herein) with the first and secondsupport plates. One of the first and second rotatable joint connectionshas at least two degrees of freedom and the other of the first andsecond rotatable joint connections has at least three degrees offreedom. For example, the first rotatable joint connection can have tworotational degrees of freedom (e.g., with respect to the “x” and “y”axes), and the second rotatable joint connection can have two rotationaldegrees of freedom (e.g., with respect to the “x” and “y” axes) and atranslational degree of freedom with respect to the rod, which allowsthe rod to slide (e.g., slidingly receive, slidingly engage, and/orslidingly couple) with respect to the second rotatable joint (e.g.,through a hole or aperture in the second rotatable joint). In anotherexample, the first rotatable joint connection can have two rotationaldegrees of freedom (e.g., with respect to the “x” and “y” axes) and atranslational degree of freedom with respect to the rod, and the secondrotatable joint connection can have two rotational degrees of freedom(e.g., with respect to the “x” and “y” axes).

The invention should not be considered limited to the particularembodiments described above, but rather should be understood to coverall aspects of the invention as fairly set out in the attached claims.Various modifications, equivalent processes, as well as numerousstructures to which the invention may be applicable, will be apparent tothose skilled in the art to which the invention is directed upon reviewof this disclosure. The claims are intended to cover such modificationsand equivalents.

What is claimed is:
 1. A method of controlling a direction of energyemitted by energy delivery devices, the method comprising: emittingenergy from each energy delivery device in an angular direction, eachenergy delivery device mechanically coupled to a first end of arespective rod that extends from a moveable plate to a stationary platealong a respective rod axis, the respective rod mechanically coupled toa respective first rotatable joint disposed at least in part in arespective hole in the stationary plate, wherein the angular directionis defined by an angle between the respective rod axis and a referenceaxis; with a positioning mechanism in mechanical communication with themoveable plate, changing a position of the moveable plate with respectto the stationary plate, the moveable plate in mechanical communicationwith each rod via a respective second rotatable joint, each secondrotatable joint disposed at least in part in a respective hole in themoveable plate, wherein a portion of each rod is slidingly engaged withthe respective second rotatable joint; rotating the respective first andsecond rotatable joints with respect to the stationary and moveableplates, respectively, each rod continuing to extend from the moveableplate to the stationary plate along the rod axis while the position ofthe moveable plate is changed; and changing the angular direction of theenergy emitted from each energy delivery device.
 2. The method of claim1, further comprising arranging each rod so that at least a portion ofthe energy from each energy delivery device passes through a focal zone.3. The method of claim 2, wherein changing the angular direction of theenergy emitted from each energy delivery device changes a location ofthe focal zone.
 4. The method of claim 1, wherein changing the positionof the moveable plate comprises moving the moveable plate parallel to aplane that is orthogonal to at least one of the respective rod axes. 5.The method of claim 1, wherein changing the position of the moveableplate comprises moving the moveable plate closer to or away from thestationary plate.
 6. The method of claim 1, wherein: each energydelivery device comprises one or more ultrasound transducer elements,and the energy emitted from each energy delivery device comprisesultrasound mechanical energy.
 7. The method of claim 6, furthercomprising adjusting the angular direction of the energy according to atreatment plan.
 8. The method of claim 7, further comprising: receiving,at a computer, magnetic resonance data of a target region in a subject,the magnetic resonance data indicating a measured angular direction ofthe ultrasound transducer elements; comparing, in the computer, themeasured angular direction of the ultrasound transducer elements with atarget angular direction in the treatment plan; and adjusting theposition of the moveable plate when the measured angular direction ofthe ultrasound transducer elements is different than the target angulardirection in the treatment plan.
 9. The method of claim 1, furthercomprising mechanically coupling a first ball to the first end of eachrod, the first ball disposed at least in part in the respective hole inthe stationary plate.
 10. The method of claim 9, further comprisingmechanically coupling a second ball to the portion of each rod, thesecond ball disposed at least in part in the respective hole in themoveable plate.
 11. The method of claim 1, wherein the portion of eachrod is slidingly engaged with the respective second rotatable joint suchthat an axial position of the rod with respect to the respective secondrotatable joint is adjustable from: (a) a first axial position withrespect to the respective second rotatable joint to (b) a second axialposition with respect to the respective second rotatable joint, whereinwith the rod in the first axial position with respect to the respectivesecond rotatable joint, a second end of the rod is a first distance fromthe respective second rotatable joint and wherein with the rod in thesecond axial position with respect to the respective second rotatablejoint, the second end of the rod is a second distance from therespective second rotatable joint, the second distance from therespective second rotatable joint being different than the firstdistance from the respective second rotatable joint.
 12. An apparatuscomprising: a plurality of energy delivery devices; a plurality of rods,each rod comprising first and second ends, the first end mechanicallycoupled to one of said energy delivery devices; a plurality of firstrotatable joints, each first rotatable joint mechanically coupled to arespective rod; a plurality of second rotatable joints, each secondrotatable joint is slidingly engaged on a portion of the respective rodsuch that an axial position of the respective rod with respect to therespective second rotatable joint is adjustable from: (a) a first axialposition with respect to the respective second rotatable joint to (b) asecond axial position with respect to the respective second rotatablejoint, wherein with the respective rod in the first axial position withrespect to the respective second rotatable joint, the second end of therespective rod is a first distance from the respective second rotatablejoint and wherein with the respective rod in the second axial positionwith respect to the respective second rotatable joint, the second end ofthe respective rod is a second distance from the respective secondrotatable joint, the second distance from the respective secondrotatable joint being different than the first distance from therespective second rotatable joint; a stationary plate comprising aplurality of stationary plate holes, each stationary plate holeconfigured to receive at least a portion of one of said first rotatablejoints to form a plurality of first rotatable joint connections, eachfirst rotatable joint rotatable with respect to the stationary plate;and a moveable plate comprising a plurality of moveable plate holes,each moveable plate hole configured to receive at least a portion of oneof said second rotatable joints to form a plurality of second rotatablejoint connections, each second rotatable joint rotatable with respect tothe moveable plate, wherein for each rod the first rotatable joint isdisposed between the second end and the second rotatable joint.
 13. Theapparatus of claim 12, wherein the stationary plate and/or the moveableplate is/are curved.
 14. The apparatus of claim 12, wherein the firstand second rotatable joints have two rotational degrees of freedom andthe second rotatable joint has a translational degree of freedom withrespect to the respective rod.
 15. The apparatus of claim 12, whereineach first rotatable joint comprises a first gimbal and each secondrotatable joint comprises a second gimbal.
 16. The apparatus of claim12, further comprising a positioning mechanism in mechanicalcommunication with the moveable plate to change a position of themoveable plate with respect to the stationary plate.
 17. The apparatusof claim 16, wherein each rod extends from the stationary plate to themoveable plate along a respective rod axis and the positioning mechanismis configured to change the position of the moveable plate within aplane that is orthogonal to at least one of the respective rod axes. 18.An apparatus comprising: a plurality of energy delivery devices; aplurality of rods, each rod comprising first and second ends, the firstend mechanically coupled to one of said energy delivery devices; aplurality of first rotatable joints, each first rotatable jointmechanically coupled to a respective rod; a plurality of secondrotatable joints, each second rotatable joint is slidingly engaged on aportion of the respective rod; a stationary plate comprising a pluralityof stationary plate holes, each stationary plate hole configured toreceive at least a portion of one of said first rotatable joints to forma plurality of first rotatable joint connections, each first rotatablejoint rotatable with respect to the stationary plate; a moveable platecomprising a plurality of moveable plate holes, each moveable plate holeconfigured to receive at least a portion of one of said second rotatablejoints to form a plurality of second rotatable joint connections, eachsecond rotatable joint rotatable with respect to the moveable plate; anda positioning mechanism in mechanical communication with the moveableplate to change a position of the moveable plate with respect to thestationary plate, the positioning mechanism comprising an x-y-zpositioner; wherein each of the rods extends from the moveable plate tothe stationary plate along a respective rod axis.
 19. The apparatus ofclaim 18, wherein each rod extends from the stationary plate to themoveable plate along a respective rod axis and the positioning mechanismis configured to change the position of the moveable plate within aplane that is orthogonal to at least one of the respective rod axes. 20.The apparatus of claim 18, wherein the first and second rotatable jointshave two rotational degrees of freedom and the second rotatable jointhas a translational degree of freedom with respect to the respectiverod.
 21. The apparatus of claim 18, wherein each first rotatable jointcomprises a first gimbal and each second rotatable joint comprises asecond gimbal.
 22. The apparatus of claim 18, wherein each secondrotatable joint is slidingly engaged on a portion of the respective rodsuch that an axial position of the respective rod with respect to therespective second rotatable joint is adjustable from: (a) a first axialposition with respect to the respective second rotatable joint to (b) asecond axial position with respect to the respective second rotatablejoint, wherein with the respective rod in the first axial position withrespect to the respective second rotatable joint, the second end of therespective rod is a first distance from the respective second rotatablejoint and wherein with the respective rod in the second axial positionwith respect to the respective second rotatable joint, the second end ofthe respective rod is a second distance from the respective secondrotatable joint, the second distance from the respective secondrotatable joint being different than the first distance from therespective second rotatable joint.